No they are not. First of all N100's amd M95 are made to diffrent standard.

The N100 and N95 designation are only standards the mask must pass to carry that designation. Manufactures can make them any way they like, aslong the meet the standards.

Some are fold flat, some have a valve, some are more comfortable than others, some have beter adjustable straps, etc. Pick one that has the features you prefer.